Caster



'March 22, 1938. w. F. HEROLD CASTER Filed Aug. 26, 1936 hz/mfii 72 z m 1 "b m m um m w u MP1. W a 2 al N 2 "a". H w n F Law LY M wnB ATTORNEY Patented Mar. 22, 1938 UNITED STATES PATENT OFFICE CASTER Application August 26, 1936, Serial No. 97,995

6 Claims.

The present invention relates to improvements in casters, and particularly heavy duty casters such as are used upon trucks or the like, an object being to provide a caster of this character of simple and extremely sturdy construction, and in which ball bearing swivelling means is provided between the horn and the mounting plate. It is particularly proposed to provide in a double ball bearing caster an annular ball bearing race forming member containing both ball races, preferably formed of hardened steel, and which is integrally connected to the horn which forms no part of the ball-races as by projection welding, the welding being at points between the two ball-races so that the hardening of the ball-race portions is not effected by the heat of the welding. A further object is to provide a caster in which double rows of ball bearings are provided and which are so arranged that the overall height of the caster I is not appreciably increased over the height of the caster having but a single row of balls.

With the above and other objects in View an embodiment of the invention is shown in the accompanying drawing and this embodiment will i i be hereinafter more fully described with reference thereto and the invention will be finally pointed out in the claims.

In the drawing:

Fig. 1 is a side elevation of a caster, according to the exemplary illustrated embodiment of the invention.

Fig. 2 is a vertical sectional view taken along the line 2--2 of Fig. 1.

Fig. 3 is a top plan view of the bearing member employed.

Fig. 4 is a sectional view thereof taken along the line 44 of Fig. 3.

Figs. 5 and 6 are fragmentary bottom plan views of modified forms of bearing members.

Fig. 7 is a plan view of a modified form of horn containing welding projections.

Similar reference characters indicate corresponding parts throughout the several figures of the drawing.

Referring to the drawing, the caster, according to the exemplary illustrated embodiment shown therein, comprises a horn consisting of a horn top portion l0 preferably of circular form having side leg portions l l--l I between which the caster wheel I2 is mounted upon an axle I3. The horn top In is fiat and is provided with a circular aperture M.

An annular bearing plate member l5 having a central aperture I6 is integrally secured to the horn top H) by projection welding, as at IT, the

plate member it being provided before assembly with the horn with a plurality of welding points l8 pressed therein and which force slight projections I 9 upon the under surface, these projections providing adequate metal for reliably 5 connecting the bearing plate member to the horn top through the welding action, the projections being thereby homogeneously joined with the metal of the horn top. The plate member I5 is provided with an upwardly extended rim flange 2i! which forms a ball-race 2! at the upper side, and is provided in surrounding relation to the aperture it, with an upwardly pressed angular portion 22 which forms a. ball-race 23 at the under side within the aperture [4 of the horn top.

As the Welding points are between the ballraces the hardening of the latter is not injuriously affected by the welding heat. The homogeneously connected circular horn top H3 and the circular bearing plate It provide between the inner 0 and outer ball-races 23 and 2| a double thickness circular reinforcing strut area, arranged between the oppositely directed stresses upon the ballraces, thereby supporting the bearing plate rigidly at its area which would otherwise tend to distort under the load imposed upon the caster. It is thus made possible to form the bearing plate and horn from sheet metal pressed to shape. without impairing the strength necessary to proper functioning of the caster under heavy loads.

The attaching top plate 24 of the caster which may be of rectangular or any other suitable shape is provided centrally with an aperture 25, and in surrounding relation to this aperture is provided with a downwardly dished annular portion 26 forming a ball-race 21 diagonally opposed to and adapted to cooperate with the ball-race 2! of the plate member 15. A threaded stud 28 is engaged in the aperture 25 and is integrally connected to the top plate by welding the head 29 of the stud thereto, as at 38.

The top plate 24 is assembled to the integrally connected horn and plate member I 5 by engaging the stud 23 downwardly through the aperture it of the plate member, a row of balls 3! being interposed in engagement with the ball-races 2| and 21. A nut 32 is engaged upon the threaded stud and is provided at its upper side with an annular ball-race surface 33 diagonally opposed to and adapted to cooperate with the ball-race 23 of the plate I5, a row of balls 34 being interposed between the plate I5 and the nut 32 in engagement with the ball-races 23 and 33. The nut is secured against rotation upon the stud by means 55 of a locking pin 35 engaged with notches 36 in the nut and with a hole in the stud.

In Figs. 5 and 6 I have shown modified forms of welding projections, the projections it in Fig. 5 being spaced and elongated and the projection if]' in Fig. 6 being continuous.

In Fig. '7 I have illustrated a modified form of horn top provided with welding projections l9, there being a, greater number at the front than at the rear trailing part to take the additional strain imposed at the front of the oflset of "he caster.

It will be observed that the caster structure according to my invention comprises, in addition to the balls, three main parts, i. e., the horn with its integrally connected bearing plate i5, the top plate 24 with its integrally connected stud 28, and the nut The manner of connecting the bearing member to the horn provides a rigid integra horn structure including bearing surfaces, and at the same time permits the bearing member to be of a different metal from the horn, and also permits the horn to be of any desired shape and size irrespective of the diameter of the bearing member.

I have illustrated and described a preferred and satisfactory embodiment of the invention, but it will be understood that changes may be made therein, within the spirit and scope thereof, as defined in the appended claims.

Having thus described my invention, what I claim and desire to sec re by Letters Patent is:

1. In a caster, a honiclu ing a circular horn top area having a central ap ure therein, a circular bearing plate member rigidly secured to said horn top and having an upwardly extending annular rim flange forming an outer ball-race at its upper si' e, and an upwardly extendin cen-- tral annular portion forming an inner baP-race at its under side and havin a central aperture coaxial with. said aperture of said horn top, said inner ball race being radially i wardly of said aperture of horn top, and se horn top forming with said bearing plate a circular reinforcing strut area surrounding said inner ball race radially inwardly of said outer ball-race, an attaching plate hav g an annular ball-race at its under side opposed to outer ball-race, balls engaged in said outer ball-race, stud means carried by said attaching plate extending downwardlythrough said aperture of aid bearing plate, ball-race means carried by said stud in opposed relation to said inner ball-race, and balls engaged in said inn r ball-race.

2. In a caster, a h inclu ing a circul r horn top area having a central ture therein, a circular bearing plate member rigidly secured to said horn top and having 11 upwardly extending annular rim flange forming an outer ball-race at its upper side, and an upwardly extending central annular portion forming an inner ball-race its under side and having a cen -al aperture coaxial with said aperture of said horn top, said inner ball race being radially inwardly of said aperture of said horn top, and said horn top forming with said bearing plate a circular reinforcing strut area surrounding said inner ball-race radially inwardly of said outer ball-race, an attaching plate having an annu i .ace at its under side opposed to said outer ball-race, balls engaged in said outer ball-race, said attaching plate having an a'erture centrally of its ball-race, a threaded stud engaged in said aperture extending downwardly through said apertures of said bearing plate and horn top and having a flange at its upper end rigidly secured to the upper surface of said attaching plate radially outwardly of said aperture, a nut secured upon said stud having a ball-race surface opposed to said inner ballrace, and balls engaged in said inner ball-race.

3. In a caster, a horn including a circular side wall and a laterally inwardly extending flange forming a circular horn top area having a central aperture therein, a bearing plate member rigidly secured to said horn top and having an upwardly extending annular rim flange forming an outer ball-race at its upper side, and an upwardly extending central annular portion forming an inner ball-race at its under side and having a central aperture coaxial with said aperture of said horn top, said inner ball race being radially inwardly of said aperture of said horn top, and said horn top forming with said bearing plate a circular reinforcing strut area surrounding said inner ball-race radially inwardly of said outer ball-race, an attaching plate having an annular ball-race at its under side opposed to said outer ball-race, balls engaged in said outer ball-race, stud means carried by said attaching plate ex tending downwardly through said aperture of said bearing plate, ball-race means carried by said stud in opposed relation to said inner ball race, and balls engaged in said inner ball-race.

In a caster, a horn including a circular horn top area having a central aperture therein, a circular bearing plate member superengaged with said horn top and having an upwardly extending annular rim flange forming an outer ball-race at its upper side, and an upwardly extending central annular portion forming an inner ball-race at its under side and having a central aperture coaxial with said aperture of said horn top, said inner ball race being radially inwardly of said aperture of said horn top, securing means rigidly connecting said bearing plate to said horn top arranged in a circle radially between said inner ball-race and said outer ball-race, said horn top forming with said bearing plate a. circular reinforcing strut area surrounding said inner ballrace radially inwardly of said outer ball-race; an attaching plate having an annular ball-race at its under side opposed to said outer ball-race, balls engaged in said outer ball-race, stud means carried by said attaching plate extending downwardly through said aperture of said bearing plate, ball-race means carried by said stud in 0pposed relation to said inner ball-race, and balls engaged in said inner ball-race.

5. In a caster, a horn including a horn top having an upper annular flange with an aperture therein, a bearing plate member secured to said horn top flange by securing means arranged in a circle, said plate member having annular bearing races inwardly and outwardly spaced from said securing means.

6. In a caster, a horn including a horn top having an upper annular flange with an aperture therein, a bearing plate member secured to said horn top flange by securing means arranged in a circle, said plate member having annular bearing races inwardly and outwardly spaced from said securing means, the total cross-sectional area of the securing means being greater at the front of said horn top flange than at the rear.

WALTER F. HEROLD. 

